1. Field of the Invention
The invention relates to a system for heating hot water for home use, and in particular to a system which utilizes the hot gases of combustion from the furnace which are normally wasted through the furnace flue and chimney. More particularly the invention relates to an improved hot water heating system in which the usual domestic hot water heater is located on an upper floor of the house and is incorporated into the heating system to more efficiently recover the heretofore wasted heat of combustion.
2. Description of the Prior Art
Various hot water heating systems are known in the art which utilize the heat of the combustion gases escaping through the furnace flue and chimney to increase the efficiency of the water heating system. However, many of these prior art systems are relatively complicated and expensive in construction and are not as efficient or reliable in operation as that believed achieved by the present invention.
Many of the prior art heat recovery systems include devices which are incorporated only in the furnace flue pipe which connects the furnace to the chimney. Examples of such devices and systems are shown in U.S. Pat. Nos. 2,143,287, 3,896,992, 4,043,014, and 4,122,801. These devices provide only a relatively small surface area of the heat exchange tubes or members in which to collect the heat from the escaping gases due to their placement in the relatively short length of furnace flue pipe.
U.S. Pat. Nos. 3,295,503 and 4,066,210 show heat recovery systems in which the heat exchange unit or equipment is located in the chimney. The system shown in U.S. Pat. No. 3,295,503 includes a water jacket which surrounds an inner flue pipe, all of which is mounted in the chimney. This may result in an extremely expensive construction to fabricate and intall, and if the water jacket develops a leak it would be expensive to repair due to its location within the chimney and the difficulty of removing it therefrom. The system shown in U.S. Pat. No. 4,066,210 uses a coiled tube which is mounted in the chimney and requires the use of two separate water tanks which are mounted in the basement of the dwelling for operation of the heating system. Thus, these two systems are believed to be considerably more expensive and difficult to operate than the present invention.